It used to be thought that in Britain no one could ever confuse class with money. This was made comically clear in the 1966 television sketch “I look down on him” involving John Cleese and Ronnies Barker and Corbett. You will recall that the 6ft 5in Cleese represented the bowler-hatted pinstripe-suited upper class, Barker (in the middle) was the successful trader in pork-pie hat and rain-coat, while the diminutive Corbett, in cloth cap and muffler, was working-class man. Barker has more money than civil servant Cleese, but says: “I still look up to him, because although I have money, I am vulgar.”

This model of class structure is not recognised by those who measure social mobility today. Every piece of academic work under that headline divides the country according to income — and the extent of social mobility is defined purely by how a family’s income moves up or down in relation to that of their fellow citizens. There is a good practical reason for this. Money is measured by numbers, and is therefore readily tabulated. Not so with breeding, or social status in the old-fashioned sense: how do you measure accents, or table manners, against the x-axis on a graph?

So although most of us might feel intuitively certain that British society today is much more open and flexible than it was 40 or 50 years ago, the statisticians insist that it isn’t and that our eyes are deceiving us. Their figures appear to show that there is less familial social mobility among Britons born in 1970 than there was for those born in 1958 – and the government is convinced that this is a scandal: last week Labour announced it was putting the former cabinet minister Alan Milburn in charge of a commission that would seek to reverse this alleged collapse in social mobility, while Harriet Harman, Labour’s deputy leader, produced a New Opportunities white paper with similar intent.

The most influential of the reports on which the government has based its call to action was produced three years ago by the Sutton Trust, an admirable organisation that seeks to promote social mobility through education. The trust’s figures break society down into four quartiles by income, and then relate a father’s income when his son was 16 to what that son earns when he in turn reaches the age of 33. Its analysis revealed that while 17% of sons born in 1958 to fathers in the bottom income quartile had managed to reach the top quartile, only 11% of sons born in 1970 had achieved the same vault across the income zones. The trust went on to point out that such a decline in “social mobility” had not been experienced by countries such as Sweden and Norway – causing more agonising in new Labour circles.

One thing that is never asked, either by the academics or the politicians, is what would be an ideal or even desirable level of social mobility. A bloody revolution along Bolshevik lines would presumably maximise social mobility (or at least make sure that the top quartile moved with astonishing rapidity downwards) but that form of economic redistribution has long been consigned to the dustbin of history.

To listen to some on the present-day left, however, you might be forgiven for thinking that we are living in a new feudal age, in which it is impossible for the ambitious worker to break out of a life of unchanging economic fortunes.

Yet even those allegedly dire Sutton Trust figures show a tremendous amount of generational movement between income brackets. For example, 62% of the sons born in 1970 to fathers in the lowest income quartile escaped into the three higher quartiles. Or, to look at it from the other end of the social telescope, only 42% of sons born in 1970 to fathers in the top income bracket retained their family’s position in the highest income quartile.

Indeed, 16% of the sons born in 1970 to the highest income quartile ended up at the bottom. In other words, there is a vast amount of social churning, at least measured by relative income. Moreover, the assertion that we have less social mobility than the Scandinavians may be based on a statistical sleight of hand. Countries such as Sweden have smaller variations in post-tax salaries; it is much easier to move in and out of their more closely bunched income quartiles, thus creating the illusion of greater social mobility.

I doubt that Harman will be too exercised by such arguments, however. As the privately educated niece of the late Earl and Countess of Longford, she seems to have a particular need to prove herself to be a campaigner against the entrenched privileges of the English class system. The same sort of politics of expiation characterised the career of Tony Benn, formerly Viscount Stansgate. Perhaps that is why such politicians seem to enrage the aspirant middle classes like no others: there is the distinct sense that these are people who, having enjoyed the fruits of selective or private education themselves, are determined to pull that ladder up behind them and leave the rest of society stagnating in undifferentiated mediocrity masquerading as egalitarianism.

The Sutton Trust itself was founded by someone who had broken through the social barriers in a particular way that would now be very much more difficult: Sir Peter Lampl was brought up on a council estate, passed the 11-plus and from grammar school went on to Oxford and then to a successful career as a financier in the United States. He was very disturbed, on his return to this country, to discover how his old Oxford college “used to have lots of ordinary Welsh kids, but they’re not coming through any more”.

Lampl will not be successful in his general aim of recreating something like the old grammar school system; David Cameron has abandoned the Conservative pledge to restore them and has adopted Tony Blair’s policy of trying to introduce some of the rigour and discipline of the private educational system within the non-selective state sector, via so-called academies.

The fact that the partially privately financed academies are loathed by the main teaching unions strongly suggests that there might be a lot to be said for them. While it is true that the destruction of the grammar school system was an act of educational vandalism, it was never going to be the answer for more than a minority, which is why it has a relatively small political constituency. The real destruction of the aspirations of what used to be called the working class was by those who claimed to be its saviours, within the comprehensive system.

A Marxist-influenced teaching profession that regarded academic rigour as a bourgeois imposition, based on an outmoded social order, betrayed an entire generation of children. As the Conservative education spokesman Michael Gove notes, while the Italian Marxist Antonio Gramsci advocated the “march through the institutions”, which his followers carried out, Gramsci himself was a deep opponent of “progressive” educational methods. He wrote: “The most paradoxical aspect is that this new type of school is advocated as being democratic, while in fact it is destined not merely to perpetuate social differences, but to crystallise them.”

It is striking that Harman and Milburn have said nothing about education, as they announce their intentions to eradicate the “privileges of the class system”. As the state schools begin increasingly to drop “difficult” GCSE subjects such as foreign languages, their natural response would be to legislate to make sure that monoglots will not be discriminated against in examinations to join the Foreign Office. Perhaps – if we are prepared to ignore the inevitable erosion of basic institutional freedoms, or even notions of excellence – they are right that this type of legislation would increase “social mobility”. But what would be the point? The problem is not so much class, as the classroom.

dominic.lawson@sunday-times.co.uk

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